Research On Vehicle Development And Pollution Characteristics Of Particulate Emissions In Beijing

With the rapid development of the city, Beijing had the largest number of motor vehicle ownership and private car quantity among big cities in our country, and maintained a fast rising trend in recent years. The sharp increase of vehicles number not only greatly increased the urban traffic pressure, but also was one of the main factors of haze weather, which had a great impact on climate change as well.Firstly, the thesis makes a detailed investigation on the vehicle ownership, types growth, and models of Beijing in recent years, collect a large amount of data and display in the form of chart, by which can conclude the development of the Beijing vehicles and predict the future trend. On this basis, we statistics and estimate the vehicle pollutants emissions of Beijing, providing the basis for making vehicle control strategy. The results show that CO₂ emissions from the transport is about 186,620,000 tons（in 2012）, about 10.6% of the total, and NO_x emissions account for about 50% of the total. thus it can be seen, there has a huge potential for energy saving and emission reduction in Beijing transportation field.Haze weather has became a new norm for Beijing now, air pollution type of Beijing has changed from coal-burning pollution in the past to mixed type pollution, particles, especially fine particulate matter, have became one of the main pollutants of atmospheric in Beijing gradually. The paper made source apportionment on PM_2.5 in Beijing by using chemical mass balance model（CMB8.2）, the results show that the dust has the highest share rate among local pollutants, up to 26.27 percent; followed by secondary particles, have a share rate of 23.11 percents, vehicle exhaust dust followed by 19.32 percents, soot dust as the fourth largest source of a share rate of 10.59 percents. Road dust, the secondary particles, vehicle exhaust dust and soot dust as the main source of PM_2.5, through the comparative study on composition of PM_2.5 in different time and space area at the same time, we analyze the change rule of the composition of PM_2.5.The thesis studies the change of PM_2.5 concentration with time and space conditions, by adopting the method of combining field monitoring and automatic monitoring, record temperature, relative humidity, wind speed, air pressure and other meteorological factors at the same time, we can study the effect factors of PM_2.5 concentrations.Vehicle exhaust emissions not only affect the atmospheric environment, but also will cause a certain impact on water and soil environment, the higher the temperature of the aqueous solution, the greater the amount of dissolved particles, the faster solution conductivity value increases. The dissolution rate of the smallest particles in the solution of p H=7.0, with the p H value to reduce or increase the dissolution rate increased gradually, and the p H value of the larger power the higher dissolution rate. Particles not only dissolve the fastest in the first three hours, but also the conductivity of the solution grow fastest at the same period.Vehicle exhaust has a great influence on the heavy metal content of soil around the roads. Paper simulates the Cu, Zn and Pb concentration in surrounding soil beside the roads, by using Surfer 8.0 software. In soil vertical section, the migration ability of three kinds of heavy metal element is:Zn>Pb>Cu. Finally, by using single index method and Nemerow index method, we evaluate the heavy metal pollution level of surrounding soil beside Beijing urban road.Based on the above research can be found that the vehicle has a great potential for energy saving and emission reduction in Beijing, and the development of vehiclea has caused a profound impact on Beijing’s environment and climate.,by which we can reduce the damage to a minimum.